Copper Alloy C55181 vs ERCuSi-A
Copper Alloy · grade comparison
Copper Alloy C55181 and ERCuSi-A are both copper alloy grades. ERCuSi-A is the stronger of the two: tensile strength 350 MPa (50.8 ksi) against 250 MPa (36.3 ksi) for C55181, about 40% more. ERCuSi-A is the more ductile: elongation 38% versus 2% for C55181, and C55181 is harder (105 HB vs 85 HB). C55181 is lighter (7.95 g/cm³ vs 8.53 g/cm³ for ERCuSi-A) and C55181 is stiffer (110 GPa vs 103 GPa). On the shop floor, ERCuSi-A welds better (excellent vs poor).
C55181Choose it when weight is the constraint.
ERCuSi-AChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
C55181 vs ERCuSi-A: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Vickers
Bulk Modulus
Yield Strength (0.2% offset)
Reduction in Area
Charpy V-Notch Impact (RT)
Hardness, Rockwell B
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Min Service Temperature
Same in both: Specific Heat Capacity 380 J/kg·K0.09 BTU/lb·°F · Max Service Temperature (continuous) 200°C392 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Machinability Rating (AISI 1212 = 100 %)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Water
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 3.8 kg CO₂/kg
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
Thermal Shock Resistance Index
Strength versus weight
Yield strength against density for every copper alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | C55181 | ERCuSi-A |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.
C55181 vs ERCuSi-A — frequently asked
Is ERCuSi-A stronger than C55181?
Yes. ERCuSi-A has a typical tensile strength of 350 MPa (50.8 ksi) against 250 MPa (36.3 ksi) for C55181 — about 40% more.
Which is cheaper, C55181 or ERCuSi-A?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, C55181 or ERCuSi-A?
ERCuSi-A, by a small margin. Both rate poor for machinability — 33/100 against 25/100 for C55181; for welding the order is ERCuSi-A first (excellent, 90/100) then C55181 (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in C55181 and ERCuSi-A side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.